For the record, I believe that most DSLRs actually have APS (24mm?) sensors. Only the high-end ones have something roughly comparable to the "35mm" file frame.
I was an early adopter of digital photography, taking many pictures, which still hold up relatively well considering they were taken with a 2 megapixel camera. I've explored limitations and utter fail in how designers of digital cameras completely missed the mark for how they would need to be used.
Largest problem was in how long it took to shift various settings around to get an optimal exposure, something which could be done in a fraction of a second on my old film camera, where practice and experience produced wonderful results. Digital cameras largely made up for this with the ability to take a lot of pictures and then keep the one you like, rather than taking about three pretty good pictures and chosing the best among them.
More recently low end digital cameras have expounded their marvelous Megapixel rating, never mind much of this was empty resolution derived from whatever a processor extrapolated a jpeg to. Image quality for a "14 megapixel" camera could be no better than my old 2 megapixel. Optical Zoom is your friend, Digital Zoom is garbage, only saving you the step of taking a picture and blowing up the interesting bit - there is no magic way to get detail from a blow-up which you didn't have before, particularly in lossy jpeg compression.
At 20 or greater Megapixel Full Frame cameras are finally getting to where higher quality film cameras resided in terms of capture. Convenience of many camera phones produces quick photos, but usually they suffer because they are noisy and rely on tiny lens rather than having the benefit of a larger sensor exposed to much more light through a far greater apperature.
Now you have a Full Frame camera, you should do all your shooting in RAW mode. Memory is cheap and you can always scale downward with Photoshop at home.